Mon·Jul 11, 2022Monday·July 11, 2022

1. 01*

   Energy Correlators of Hadronically Decaying Electroweak Bosons

   Lorenzo Ricci🇨🇭 · Marc Riembau🇨🇭

   Energy correlators are field-theoretically clean and phenomenologically valuable probes of QCD dynamics. We explore the possibility of using the information encoded in the energy correlators of a hadronically decaying electroweak vector boson in order to extract its full decay density matrix. The kinematics of the one- and two-point energy correlators can indeed discriminate between longitudinal and transverse modes and reveal the interference pattern between different vector polarizations. Such observables improve the sensitivity to microscopic new physics affecting the production rate of the different helicities. We assess the impact on higher dimensional EFT operators in simple scenarios.

   hep-phhep-exPRD(2022)·25 citations
2. 02*

   One-Loop Corrections to Dihadron Production in DIS at Small $x$

   Filip Bergabo🇺🇸 · Jamal Jalilian-Marian🇺🇸

   We calculate the one-loop corrections to dihadron production in Deep Inelastic Scattering (DIS) at small x using the Color Glass Condensate formalism. We show that all UV and soft singularities cancel while the collinear divergences are absorbed into quark and anti quark-hadron fragmentation functions. Rapidity divergences lead to JIMWLK evolution of dipoles and quadrupoles describing multiple-scatterings of the quark anti-quark dipole on the target proton/nucleus. The resulting cross section is finite and can be used for phenomenological studies of dihadron angular correlations at small x in a future Electron-Ion Collider (EIC).

   hep-phnucl-thPRD(2022)·55 citations
3. 03*

   Nuclear geometry at high energy from exclusive vector meson production

   Heikki Mäntysaari🇫🇮 · Farid Salazar🇺🇸 · Björn Schenke🇺🇸

   We show that when saturation effects are included one obtains a good description of the exclusive $\mathrm{J}/\psi$ production spectra in ultra peripheral lead-lead collisions as recently measured by the ALICE Collaboration at the LHC. As exclusive spectra are sensitive to the spatial distribution of nuclear matter at small Bjorken-$x$, this implies that gluon saturation effects modify the impact parameter profile of the target as we move towards small $x$. In addition to saturation effects, we find a preference for larger nuclear strong-interaction radii compared to the typical charge radius. We demonstrate the role of finite photon transverse momentum and the interference between the cases for which the role of photon emitter and target are switched between the nuclei. We show that these effects are comparable to the experimental precision for $p_T$-differential cross sections and as such need to be included when comparing to LHC data. Finally, the integrated $\mathrm{J}/\psi$ production cross sections from the LHC and preliminary transverse momentum spectra from RHIC are shown to prefer calculations with fluctuating nucleon substructure, although these datasets would require even stronger saturation effects than predicted from our framework.

   hep-phnucl-thPRD(2022)·81 citations
4. 04*

   Module Intersection and Uniform Formula for Iterative Reduction of One-loop Integrals

   Jiaqi Chen🇨🇳 · Bo Feng🇨🇳

   In this paper, we develop an iterative sector-level reduction strategy for Feynman integrals, which bases on module intersection in the Baikov representation and auxiliary vector for tensor structure. Using this strategy we have studied the reduction of general one-loop integrals, i.e., integrals having arbitrary tensor structures and arbitrary power for propagators. Inspired by these studies, a uniform and compact formula that iteratively reduces all one-loop integrals has been written down, where messy polynomials in integration-by-parts (IBP) relations have organized themselves to Gram determinants.

   hep-phJHEP(2023)·11 citations
5. 05*

   Two-loop improved predictions for $M_W$ and ${\sin }^2{\theta }_{eff}$ in Two-Higgs-Doublet Models

   Stephan Hessenberger🇩🇪 · Wolfgang Hollik🇩🇪

   We present the currently most precise predictions for the $W$-boson mass and the leptonic effective mixing angle ${\sin }^2{\theta }_{\text{eff}}$ in the aligned Two-Higgs-Doublet Model. The evaluation includes the full one-loop result, all known higher-order corrections of the Standard Model, and the non-standard two-loop contributions that increase with mass splittings between charged and neutral THDM Higgs bosons. They depend on $\tan \beta$ and the soft $Z_2$-symmetry breakingparameter $m_{12}^2$ of the scalar potential, in addition to the non-standard boson masses. Whenever the one-loop corrections become large, the two-loop contributions yield substantial modifications of the predictions, which is of particular importance for the $W$ mass where large mass shifts are required to reach the recently published final resultof the CDF collaboration. Numerical results are shown for the dependence on the various non-standard parameters and in comparison with experimental data.

   hep-phEPJC(2022)·19 citations
6. 06*

   Probing non-standard $HVV(V=W,Z)$ couplings in single Higgs production at future electron-proton collider

   Pramod Sharma🇮🇳 · Ambresh Shivaji🇮🇳

   The couplings of the Higgs boson ($H$) with massive gauge bosons of weak interaction ($V=W,Z$), can be probed in single Higgs boson production at the proposed future Large Hadron-Electron Collider (LHeC). In the collision of an electron with a proton, single Higgs production takes place via so-called charged-current ($e^{-}p\to {\nu }_{e}Hj$) and neutral-current ($e^{-}p\to e^{-}Hj$) processes. We explore the potential of the azimuthal angle correlation between the forward jet and scattered neutrino or electron in probing the non-standard $HVV$ couplings at the collider center-of-mass energy of $\sqrt{s}\approx 1.3$~TeV. We choose the most general modifications (of $CP$-even and $CP$-odd nature) to these couplings due to new physics effects beyond the standard model. We derive exclusion limits on new physics parameters of $HVV$ couplings as a function of integrated luminosity at $95\%$ C.L. using the azimuthal angular correlations in charged- and neutral-current processes. We find that using 1000 $f{b}^{-1}$ data, the standard model-like new physics parameters in $HWW$ and $HZZ$ couplings can be constrained with accuracies of $4\%$ and $15\%$, respectively. The least constrained $CP$-even parameters of $HWW$ coupling can be as large as 0.04, while those of $HZZ$ coupling can have values around 0.31. Allowed values of $CP$-odd parameters in $HWW$ and $HZZ$ couplings are found to be around 0.14 and 0.34, respectively. We also study changes in the allowed values of non-trivial new physics parameters in the presence of other parameters.

   hep-phhep-exJHEP(2022)·16 citations
7. 07*

   The possibility of $X(4014)$ as a $D^{\ast }{\bar{D}}^{\ast }$ molecular state

   Man-Yu Duan🇨🇳 · Dian-Yong Chen🇨🇳 · En Wang🇨🇳

   Within the framework of the local hidden gauge approach, we have studied the near-threshold interaction of the $D^{\ast }{\bar{D}}^{\ast }$ channel with quantum numbers $I(J^{PC})=0(0^{++})$, $0(2^{++})$, $1(0^{++})$, and $1(2^{++})$, respectively. The contact interaction is taken into account alone, since it is expected to give the dominant contribution near the threshold. One pole, which is found in the case of the quantum numbers $I(J^{PC})=0(0^{++})$, could be associated to the $X(4014)$ recently observed by the Belle Collaboration. Thus, we suggest that the $X(4014)$ may be an $D^{\ast }{\bar{D}}^{\ast }$ molecular state with $I(J^{PC})=0(0^{++})$, and more precise information about $X(4014)$, such as resonance parameters and decay properties, could be useful to shed light on its structure.

   hep-phEPJC(2022)·14 citations
8. 08*

   Neutrino oscillations in gravitational fields and astrophysical applications

   Maxim Dvornikov (IZMIRAN)🇷🇺

   The neutrino propagation and oscillations in various gravitational fields are studied. First, we consider the neutrino scattering off a black hole accounting for the neutrino spin precession. Then, we study the evolution of flavor neutrinos in stochastic gravitational waves. The astrophysical applications of the obtained results are considered.

   hep-phastro-ph.HEgr-qcMoscow Univ.Phys.Bull.(2022)·3 citations
9. 09*

   Singular properties of QED vacuum response to applied quasi-constant electromagnetic fields

   Stefan Evans🇺🇸 · Johann Rafelski🇺🇸

   Employing the Bogoliubov coefficient summation method and introducing the gyromagnetic ratio $g\ne 2$ we derive an explicit functional form of $\mathfrak{Im}{V}_g^{\mathrm{EHS}}$, the imaginary part of Euler-Heisenberg-Schwinger (EHS) type effective action. We show that $\mathfrak{Im}{V}_g^{\mathrm{EHS}}$ is periodic in $g$ for any (quasi-)constant electromagnetic field configuration, and equal to the imaginary part obtained using a periodic in $g$ Ramanujan integrand in the proper time representation of $V_g^{\mathrm{EHS}}$. This validates the Ramanujan representation of $V_g^{\mathrm{EHS}}$ for both real and imaginary parts and allows writing the effective action in a suitably modified Schwinger proper time format. As a function of the ratio $b/a$ between $\mathcal{B}\to b$ and $\mathcal{E}\to a$ covariant generalizations of EM fields, we explore the singular properties of $\mathfrak{Im}{V}_g^{\mathrm{EHS}}$ at $g=2\pm 4k,k=0,\pm 1,\pm 2\dots$ involving the pseudoscalar $ab\equiv \vec{\mathcal{E}}\cdot \vec{\mathcal{B}}$ in perturbative and nonperturbative behavior. We study the $e^{-}{e}^{+}$-decay vacuum instability, incorporating the physical value of $g-2$ vertex diagrams when summing infinite irreducible loops. We obtain an effective expansion parameter ${\chi }_b=\alpha b/2a$ ($\alpha =e^2/4\pi$), characterizing the onset of nonperturbative in $g-2$ suppression of vacuum instability. We demonstrate the ${\chi }_b$ domains for which perturbative expansion in $\alpha$ breaks down: The EM vacuum subject to critical electric field strength is stabilized in magnetic-dominated \lq magnetar\rq\ environments. Considering separately the case of $\mathcal{E}$ and $\mathcal{B}$ fields, we generalize to all $g$ the temperature representation of the $V_g^{\mathrm{EHS}}$ effective action.

   hep-ph1 citation
10. 10*

    Tripling down on the $W$ boson mass

    Henning Bahl🇺🇸 · Wen Han Chiu🇺🇸 · Christina Gao🇺🇸 · Lian-Tao Wang🇺🇸 · Yi-Ming Zhong🇺🇸

    A new precision measurement of the $W$ boson mass has been announced by the CDF collaboration, which strongly deviates from the Standard Model prediction. In this article, we study the implications of this measurement on the parameter space of the $SU(2{)}_L$ triplet extension (with hypercharge $Y=1$) of the Standard Model Higgs sector, focusing on a limit where the new triplet is approximate ${\mathbb{Z}}_2$-odd while the SM is ${\mathbb{Z}}_2$-even. We study the compatibility of the triplet spectrum preferred by the $W$ boson mass measured by the CDF-II experiment with other electroweak precision observables and Higgs precision data. We comprehensively consider the signals of new Higgs states at the LHC and highlighted the promising search channels. In addition, we also investigate the cosmological implications of the case in which the lightest new Higgs particle is either late decaying or cosmologically stable.

    hep-phEPJC(2022)·36 citations
11. 11*

    Gravitational Waves from Current-Carrying Cosmic Strings

    Pierre Auclair🇧🇪 · Simone Blasi🇧🇪 · Vedran Brdar🇺🇸 · Kai Schmitz🇨🇭

    Cosmic strings are predicted by many Standard Model extensions involving the cosmological breaking of a symmetry with nontrivial first homotopy group and represent a potential source of primordial gravitational waves (GWs). Present efforts to model the GW signal from cosmic strings are often based on minimal models, such as, eg, the Nambu--Goto action that describes cosmic strings as exactly one-dimensional objects without any internal structure. In order to arrive at more realistic predictions, it is therefore necessary to consider nonminimal models that make an attempt at accounting for the microscopic properties of cosmic strings. With this goal in mind, we derive in this paper the GW spectrum emitted by current-carrying cosmic strings (CCCSs), which may form in a variety of cosmological scenarios. Our analysis is based on a generalized version of the velocity-dependent one-scale (VOS) model, which, in addition to the mean velocity and correlation length of the string network, also describes the evolution of a chiral (light-like) current. As we are able to show, the solutions of the VOS equations imply a temporarily growing fractional cosmic-string energy density, ${\Omega }_{\mathrm{cs}}$. This results in an enhanced GW signal across a broad frequency interval, whose boundaries are determined by the times of generation and decay of cosmic-string currents. Our findings have important implications for GW experiments in the Hz to MHz band and motivate the construction of realistic particle physics models that give rise to large currents on cosmic strings.

    ↳ astro-ph.COhep-phJCAP(2023)·33 citations
12. 12*

    Fast Flavor Transformations

    Sherwood Richers🇺🇸 · Manibrata Sen🇩🇪

    The neutrino fast flavor instability (FFI) can change neutrino flavor on time scales of nanoseconds and length scales of centimeters. It is expected to be ubiquitous in core-collapse supernovae and neutron star mergers, potentially modifying the neutrino signal we see, how matter is ejected from these explosions, and the types of heavy elements that form in the ejecta and enrich the universe. There has been a great deal of recent interest in understanding the role the FFI plays in supernovae and mergers, but the short length and time scales and the strong nonlinearity have prevented the FFI from being included consistently in these models. We review the theoretical nature of the FFI starting with the quantum kinetic equations, where the instability exists in neutron star mergers and supernovae, and how the instability behaves after saturation in simplified simulations. We review the proposed methods to test for instability in moment-based calculations where the full distribution is not available and describe the numerical methods used to simulate the instability directly. Finally, we close by outlining the trajectory toward realistic, self-consistent models that will allow a more complete understanding of the impact of the FFI in supernovae and mergers.

    ↳ astro-ph.HEhep-ph81 citations
13. 13*

    Time delays, choice of energy-momentum variables and relative locality in doubly special relativity

    J. M. Carmona🇪🇸 · J. L. Cortés🇪🇸 · J. J. Relancio🇪🇸 · M. A. Reyes🇪🇸

    Doubly Special Relativity (DSR) theories consider (quantum-gravity motivated) deformations of the symmetries of special relativity compatible with a relativity principle. The existence of time delays for massless particles, one of their proposed phenomenological consequences, is a delicate question, since, contrary to what happens with Lorentz Invariance Violation (LIV) scenarios, they are not simply determined by the modification in the particle dispersion relation. While some studies of DSR assert the existence of photon time delays, in this paper we generalize a recently proposed model for time delay studies in DSR and show that the existence of photon time delays does not necessarily follow from a DSR scenario, determining in which cases this is so. Moreover, we clarify long-standing questions about the arbitrariness in the choice of the energy-momentum labels and the independence of the time delay on this choice, as well as on the consistency of its calculation with the relative locality paradigm of DSR theories. Finally, we show that the result for time delays is reproduced in models that consider propagation in a noncommutative spacetime.

    ↳ gr-qchep-phhep-thPRD(2022)·14 citations
14. 14*

    QFT approach to dressed particle processes in preheating and non-perturbative mechanism in kinematically-forbidden regime

    Hidetoshi Taya🇯🇵 · Yusuke Yamada🇯🇵

    We provide a quantum-field theoretic formulation of dressed particle dynamics that systematically include particle production and scattering/decay processes in the preheating era. Our approach is based on the so-called perturbation theory in the Furry picture, in which coherent background fields (i.e., inflaton and the expanding Universe) are treated non-perturbatively whereas interactions between dressed particles are taken into account perturbatively. As application, we consider the instant preheating mechanism and compute the number of produced particles explicitly, assuming that the coherent fields are adiabatic. We find a novel non-perturbative particle-production mechanism, which is kinematically forbidden within the conventional perturbative calculation and produces particles exponentially efficiently than the perturbative one does.

    ↳ hep-thgr-qchep-phJHEP(2023)·4 citations
15. 15*

    Condensation and Evaporation of Boson Stars

    James Hung-Hsu Chan🇺🇸 · Sergey Sibiryakov🇨🇦 · Wei Xue🇺🇸

    Axion-like particles, including the QCD axion, are well-motivated dark matter candidates. Numerical simulations have revealed coherent soliton configurations, also known as boson stars, in the centers of axion halos. We study evolution of axion solitons immersed into a gas of axion waves with Maxwellian velocity distribution. Combining analytical approach with controlled numerical simulations we find that heavy solitons grow by condensation of axions from the gas, while light solitons evaporate. We deduce the parametric dependence of the soliton growth/evaporation rate and show that it is proportional to the rate of the kinetic relaxation in the gas. The proportionality coefficient is controlled by the product of the soliton radius and the typical gas momentum or, equivalently, the ratio of the gas and soliton virial temperatures. We discuss the asymptotics of the rate when this parameter is large or small.

    ↳ astro-ph.COhep-phhep-thJHEP(2024)·41 citations
16. 16*

    Neutrino Flavor Conversion, Advection, and Collisions: Towards the Full Solution

    Shashank Shalgar🇩🇰 · Irene Tamborra🇩🇰

    At high densities in compact astrophysical sources, the coherent forward scattering of neutrinos onto each other is responsible for making the flavor evolution non-linear. Under the assumption of spherical symmetry, we present the first simulations tracking flavor transformation in the presence of neutrino-neutrino forward scattering, neutral and charged current collisions with the matter background, as well as neutrino advection. We find that, although flavor equipartition could be one of the solutions, it is not a generic outcome, as often postulated in the literature. Intriguingly, the strong interplay between flavor conversion, collisions, and advection leads to a spread of flavor conversion across the neutrino angular distributions and neighboring spatial regions. Our simulations show that slow and fast flavor transformation can occur simultaneously. In the light of this, looking for crossings in the electron neutrino lepton number as a diagnostic tool of the occurrence of flavor transformation in the high-density regime is a limiting method.

    ↳ astro-ph.HEhep-phPRD(2023)·58 citations
17. 17*

    Global view of neutrino interactions in cosmology: The freestreaming window as seen by Planck

    Petter Taule🇩🇪 · Miguel Escudero🇩🇪 · Mathias Garny🇩🇪

    Neutrinos are expected to freestream (i.e. not interact with anything) since they decouple in the early Universe at a temperature $T\sim 2\mathrm{MeV}$. However, there are many relevant particle physics scenarios that can make neutrinos interact at $T<2\mathrm{MeV}$. In this work, we take a global perspective and aim to identify the temperature range in which neutrinos can interact given current cosmological observations. We consider a generic set of rates parametrizing neutrino interactions and by performing a full Planck cosmic microwave background (CMB) analysis we find that neutrinos cannot interact significantly for redshifts $2000\lesssim z\lesssim 10^5$, which we refer to as the freestreaming window. We also derive a redshift dependent upper bound on a suitably defined interaction rate ${\Gamma }_{\text{nfs}}(z)$, finding ${\Gamma }_{\text{nfs}}(z)/H(z)\lesssim 1-10$ within the freestreaming window. We show that these results are largely model independent under some broad assumptions, and contextualize them in terms of neutrino decays, neutrino self-interactions, neutrino annihilations, and majoron models. We provide examples of how to use our model independent approach to obtain bounds in specific scenarios, and demonstrate agreement with existing results. We also investigate the reach of upcoming cosmological data finding that CMB Stage-IV experiments can improve the bound on ${\Gamma }_{\text{nfs}}(z)/H(z)$ by up to a factor $10$. Moreover, we comment on large-scale structure observations, finding that the ongoing DESI survey has the potential to probe uncharted regions of parameter space of interacting neutrinos. Finally, we point out a peculiar scenario that has so far not been considered, and for which relatively large interactions around recombination are still allowed by Planck data due to some degeneracy with $n_s$, $A_s$ and $H_0$. This scenario can be fully tested with CMB-S4.

    ↳ astro-ph.COhep-phPRD(2022)·31 citations

* Reconstructed cohort: no mailing for this day survives in the archive. Papers are grouped by their submission times and arXiv's announcement cut-off, assuming announcement without delay; positions follow identifier order. Validated at ~91% exact-day agreement against the archived era.